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+/* Compute maximum of two numbers, regarding NaN as missing argument.
+ Copyright (C) 1997-2017 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+ .text
+ENTRY(__fmaxl)
+ fldt 16(%esp) // y
+ fxam
+ fnstsw
+ fldt 4(%esp) // y : x
+
+ andb $0x45, %ah
+ cmpb $0x01, %ah
+ je 2f // y == NaN
+
+ fxam
+ fnstsw
+ andb $0x45, %ah
+ cmpb $0x01, %ah
+ je 3f // x == NaN
+
+ fucom %st(1)
+ fnstsw
+ sahf
+ jnc 1f
+
+ fxch %st(1)
+1: fstp %st(1)
+
+ ret
+
+2: // st(1) is a NaN; st(0) may or may not be.
+ fxam
+ fnstsw
+ andb $0x45, %ah
+ cmpb $0x01, %ah
+ je 4f
+ // st(1) is a NaN; st(0) is not. Test if st(1) is signaling.
+ testb $0x40, 23(%esp)
+ jz 4f
+ fstp %st(1)
+ ret
+
+3: // st(0) is a NaN; st(1) is not. Test if st(0) is signaling.
+ testb $0x40, 11(%esp)
+ jz 4f
+ fstp %st(0)
+ ret
+
+4: // Both arguments are NaNs, or one is a signaling NaN.
+ faddp
+ ret
+END(__fmaxl)
+weak_alias (__fmaxl, fmaxl)